About Supported Transactions
Supported transactions have a legitimate reason for having no match.
You can enter an explanation to justify them as correct and valid despite having no match. For example, a user can flag a transaction as legitimately unmatched (for example, to account for timing differences that are appropriate at a specific point in time).
Supporting details, entered by the preparer explaining the valid reason for not matching during Auto Match, are retained in Account Reconciliation after the transaction is matched. Once a supported transaction is matched, the status changes to Confirmed Match, but the support is retained. If a matched transaction, which is already supported, is then unmatched on the Match dialog, it goes back to Unmatched Supported status.
Supporting details are tied to the workflow of the period end reconciliation. If a preparer deletes transaction matching supporting details that are associated with a period-end reconciliation, then that period-end reconciliation will be re-opened to the preparer. Preparers can still add comments or file attachments to existing supporting details, it is only the removal of details that would cause a reconciliation to re-open.